CVE-2026-74490 tipc: avoid use-after-free in poll trace queue dumps
A use-after-free vulnerability in the Linux kernel TIPC module allows attackers to cause denial of service or potentially execute code via race conditions in poll trace queue dumps.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74490?
CVE-2026-74490 is a high-severity use after free vulnerability in Linux, published on 15 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
tipc: avoid use-after-free in poll trace queue dumps
TIPC socket tracepoints dump queue state through tipc_sk_dump(). Most queue-dump callsites already serialize that walk under the socket lock or sk->sk_lock.slock, but tipc_poll() calls trace_tipc_sk_poll(..., TIPC_DUMP_ALL, ...) without holding either lock.
That lets the poll trace path reach tipc_list_dump() and backlog head/tail dumping while another context dequeues and frees an skb, leaving the trace helper dereferencing a stale queue entry.
Stop the unlocked poll trace site from requesting queue dumps. Other queue dump trace callsites keep their existing output under the locking they already provide, while poll still emits the event itself without walking live queue members from an unlocked context.
Which versions are affected by CVE-2026-74490?
How do I fix CVE-2026-74490?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-74490 being exploited?
There is no known exploitation of CVE-2026-74490 in the wild and no public exploit code.
Sources
Also known as AZL-96378, BELL-CVE-2026-74490, DEBIAN-CVE-2026-74490, GHSA-5445-w6x8-6hfq, UBUNTU-CVE-2026-74490.